Reduction of selenite and selenate on anoxically corroded iron and the synergistic effect of uranyl reduction
2010 (English)In: Journal of Nuclear Materials, ISSN 0022-3115, E-ISSN 1873-4820, Vol. 406, no 2, 230-237 p.Article in journal (Refereed) Published
In this work the uptake of dissolved selenium in the form of selenite and selenate on iron covered by amagnetite corrosion layer and the effect of dissolved uranyl on this process is studied. Under simulatedanoxic groundwater conditions (bicarbonate and chloride solutions) no immobilization of selenate was found in the absence of uranyl whereas selenite was immobilized, albeit slowly. When uranyl was present, it was found to become reduced and greatly enhanced the rate of reductive immobilization of the dissolved selenite as well as selenate. The increased rate of immobilization is proposed to be due to the oxidative transformation of the passifying magnetite layer as the uranyl is reduced with the observed formation of a transient mixed Fe(II)/Fe(III) oxyhydroxide phase. The iron oxide, and selenium speciation on the surfaces were investigated by Raman spectroscopy. X-ray Absorption Spectroscopy was used to determine the oxidation state of the selenium and uranium on the surfaces.
Place, publisher, year, edition, pages
2010. Vol. 406, no 2, 230-237 p.
Anoxic groundwater, Chloride solutions, Corrosion layers, Magnetite layers, Oxidation state, Oxidative transformations, Oxyhydroxides, Reductive immobilization, Selenium speciation, Synergistic effect, Chlorine compounds, Dissolution, Groundwater, Iron oxides, Magnetite, Raman spectroscopy, Selenium, Selenium compounds, Uranium, Uranium alloys
IdentifiersURN: urn:nbn:se:kth:diva-26993DOI: 10.1016/j.jnucmat.2010.08.031ISI: 000284303100005ScopusID: 2-s2.0-77957864218OAI: oai:DiVA.org:kth-26993DiVA: diva2:373745
QC 201012082010-12-012010-12-012011-11-07Bibliographically approved